1. Field
The invention pertains to protective headgear, and in particular, to protective helmets which substantially completely surround the wearer's head for maximum protection during sand blasting, steam cleaning, welding, and other operations requiring protection from dust, fumes, gases and other dangerous environmental conditions. 2. State of the Art
Protective headwear must be provided during various industrial operations such as sand blasting, steam and high pressure water cleaning, welding, etc. In U.S. Pat. No. 3,181,532, issued on May 4, 1965, a protective helmet is disclosed comprising a substantially rigid hemispherical dome having a support system therein adapted to rest upon the head of a wearer. A generally cylindrical and open ended transparent shield is secured to and extends downwardly from the periphery of the dome so as to substantially completely surround the wearer's head. An upstanding hollow spindle extends from the top of the dome and is in flow communication with an air distributor within the dome. An air supply hose is connected to the spindle to supply air to the distributor in the dome. Although the helmet of U.S. Pat. No. 3,181,532 advanced the state of the art, it had, unfortunately, several deficiencies which has hindered its use commercially. The hose connection to the dome of the helmet was awkward and prone to become entangled. More serious, however, was the noise problem created by the volume of pressurized air passing through the air distributor in the dome. When sufficient air to provide proper air circulation around the head of the wearer is supplied to the distributor shown in U.S. Pat. No. 3,181,532, noise levels on the borderline or in excess of the permissable level as established by federal regulation are produced. In addition, the helmet of U.S. Pat. No. 3,181,532 was not adapted to use during welding operations.
3. Objectives
A principal objective of the present invention is to provide an improved protective helmet of the type disclosed in U.S. Pat. No. 3,181,532 wherein adequate air is supplied to the helmet for proper ventilation and circulation about the head of the wearer without creating excessive noise in the helmet due to the distribution of the air. A further objective is to provide such a protective helmet in which the air supply hose enters the helmet from the downwardly facing open end thereof, with the supply hose being anchored to a belt around the wearer's waist. Additional objectives of the invention are to supply a removable transparent sheet of material over the transparent portion of the helmet, to provide an attachment for the helmet whereby the helmet is easily converted to use as a welder's helmet, and to provide an apron or skirt which is adpated to hang from the helmet over the shoulders and upper torso portion of the wearer's body, with improved means for removably securing the apron to the helmet and for anchoring the lower portion of the apron to a belt around the wearer's waist to prevent the apron from blowing up around the helmet and obstructing the wearer's visibility. A further objective is to provide a removable filter element in combination with the air distributing means inside the helmet.